This invention relates to an alarm device which can signal an unauthorized entry into an enclosure such as a building or a vehicle. More particularly, this invention relates to a self-energized alarm unit which operates independently of an external power source and can be activated by means of a standard slide bolt for a door latch.
Alarm devices of the type concerned with in this invention are described in U.S. Pat. Nos. 3,340,522; 3,406,386; 3,444,546; 3,553,721; 3,569,950; 3,585,625; 3,560,952 and 3,714,644. All of the devices described in these patents utilize an electrical power source such as a battery. These types of energized alarm devices can and do pose problems from a dependability standpoint in that the source of electrical power can fail, such as a battery going dead without knowledge of the user. A vibration sensing component is described in U.S. Pat. No. 3,340,522 and whereas a biased switch housing is utilized in U.S. Pat. No. 3,406,386 and 3,553,721. In U.S. Pat. No. 3,444,546 a specific circuitry or key lock mechanism is utilized, and in U.S. Pat. No. 3,569,950 a slide bolt alarm is indicated for use with a resilient arm and an electrical circuit. The same general type of slide bolt electrical combination is described in U.S. Pat. No. 3,585,625, and a sepcific guide member is utilized in U.S. Pat. No. 3,560,952. A slide bolt alarm device is portrayed in U.S. Pat. No. 3,714,644 in combination with a latch mechanism having a flexible conductive member.
The prior art nowhere teaches an alarm device which is operable without the use of electrical potential and is self-energized. Neither is there available an alarm device which is energized by a spring biasing means in combination with a slide bolt latch mechanism. The prior art provides alarm mechanisms which utilize electrical circuitry and specific mechanisms for use in combination with the circuitry or specific actuating components.
It is an advantage of the present invention to provide an alarm device which can be self-energized. Other advantages are: an alarm device which is operable in combination with a door slide bolt latch mechanism; an alarm device which will operate without the use of electrical energy, and a combined latch and alarm unit which can be fabricated from standard component parts and thus is economical to manufacture.